1. Field
The present invention relates to a reference sphere detecting device, to a reference sphere position detecting device provided with the reference sphere detecting device, and to a three-dimensional-coordinate measuring device provided with the reference sphere position detecting device.
2. Description of Related Art
There has recently been increased demand for measurement of the three-dimensional shape of objects through the use of various sensors (non-contact sensors). These sensors are attached to a mechanism that can be controlled in five or six axes so as to be able to move parallel to and rotate about each of the x, y, and z axes. There have been numerous examples of techniques in which sensors for measuring the three-dimensional shape of a measured object are attached to a robotic arm, and the shape is measured from various positions and angles. Particularly in a case in which a sensor is attached to a robotic arm, unless data are associated based on an accurate assessment of the position and orientation of the sensor, the three-dimensional shape cannot be ascertained with high precision. As an example of such a case, a device has been disclosed in which a plurality of cameras capable of imaging in the entire range of movement of a sensor is used to measure the position and orientation of the sensor by analyzing the images of each camera (stereo photography method) (see Patent Document 1, for example).
Patent Document 1: Japanese Laid-Open Patent Publication No. H8-51083 based on PCT International Application No. PCT/NO94/00096